-
Color correction question – pure knowledge needed (G)
I have done a video, with many interviews. All the clips have been color corrected to what looks good on *all* HD and SD screens I’ve looked at them on. BUT: I have been showing this video all over the area, on many different projectors. I have been seeing, on *some* of the clips, significant color shift to the yellow/orange (tungsten like) on some of the projectors. These particular clips were shot with a light box illuminating them (cool flourescent with the camera white balanced when setting up the shot). To repeat, they look fine on my monitors, and all HD monitors I’ve shown them on, including various different computers and computer computer monitors. It’s only on these low end projectors do I see it, and it’s dramatic.
Any ideas when I pull up color correction, of what to be looking for in this? I assume some underlying color is ‘hiding’ and I’m unsure what it could be. I’m suspecting that some ‘tungsten bleed’ occured from the indoors lighting in the rooms, and that it’s somehow ‘hiding’ under the balance and shows up with low end projector lights? If that’s true, should I be seeing it somewhere on the tools that Vegas has to deal with color balance?
Or is this just a problem with low end projectors, that you can’t *tune* to them? Obviously, commercial high end movies are doing something to avoid this.
Alf
-
4 Replies
-
Pull up the scopes and make sure that *some* of the clips are not exceeding the legal range 255. Or simply throw on broadcast safe filter. This will require a slight adjustment in your curves and saturation again but it will balance the color range for everthing projected.
Good Luck
-
Thanks VERY much. This is the kind of info I needed.
Alf
-
Hi Alf,
Do I understand it right if I say that you are projecting your movie always from the same PC, and that the things which change are the devices you connect to your PC (different screens or projectors)?
If I get you right, then the missing thing might be an ICC profile corresponding to your output device. Maybe you already know all the following, please forgive me if yes.
Colors should be managed at different places in the production chain:
– input device, like what you did with the color balance of your camera
– storage, if you make color operations (like with my white balance plug-in – if you omitted to set the WB when shooting), you have to make sure the color changes are made in the right color space (Adobe, sRGB, …).
– and output. a given “mathematical” colour like (e.g. 220,158,63) stored in the movie file is not rendered the same by all the devices, due to slight electronical components differences. When color accuracy is an issue, adjustement should be done through an ICC profile adapted to each output device. This can usually be specified in the display properties of Windows or in your video card driver. A decent ICC profile of your device model can sometimes be downloaded from the manufacturer web site. Or you can use a calibrating tool, which sends different colors, measures the colors output by your device, compares them back with the input RGB values sent to the device, computes a mathematical transformation so that output actually corresponds to input, after the input has been transformed. This mathematical transformation is then saved to an ICC file, that you can attach to your video card. Hope I am clear enough…
When you say that mainstream movies don’t have the problem, did you try to project them from your PC, and check the output to the screens/projectors you mention?
For photography, my life has changed when I started using ICC profiles to calibrate my screens and printers: I could not have matching colors between both before – and I don’t know this issue any more now 🙂
Hope this helps,
Frédéric—
Looking for a white balance plug-in? Visit my web site.Want to learn on Sony Vegas Event Pan/Crop tool? Watch my video tutorial:
https://library.creativecow.net/baumann_frederic/Sony-Vegas_event-pan-crop-tool/1Or about Keyframes? https://library.creativecow.net/articles/baumann_frederic/Animating-with-Keyframes-in-Sony-Vegas.php
French version: https://geo.creativecow.net/fr/a/12999
-
Do I understand it right if I say that you are projecting your movie always from the same PC, and that the things which change are the devices you connect to your PC (different screens or projectors)?
Alf says: Yes.
If I get you right, then the missing thing might be an ICC profile corresponding to your output device. Maybe you already know all the following, please forgive me if yes.
(contents snipped ) – Alf says: Thanks. I will work on that.
When you say that mainstream movies don’t have the problem, did you try to project them from your PC, and check the output to the screens/projectors you mention?
Alf says: yes. It had to be my footage.
Thanks!
Alf
Reply to this Discussion! Login or Sign Up